topic "Global Value Cache";
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[{_}%EN-US 
[ {{10000@(113.42.0) [s0; [*@7;4 Global Value Cache]]}}&]
[s0; &]
[s0; Global Value Cache is a centralized mechanism to cache data. 
Items in the cache are of Value type. Global Value Cache adjusts 
its size based on current system memory consumption.&]
[s0;* &]
[ {{10000F(128)G(128)@1 [s0; [* Function List]]}}&]
[s3; &]
[s5;:Upp`:`:MakeValue`(Upp`:`:ValueMaker`&`): [_^Upp`:`:Value^ Value]_[* MakeValue]([_^Upp`:`:ValueMaker^ V
alueMaker][@(0.0.255) `&]_[*@3 m])&]
[s2; Requests a Value. The Value is defined by instance of class 
derived from ValueMaker, which is class with two virtual methods:&]
[s2; &]
[s2; virtual String [* Key]() const;&]
[s2; virtual int [* Make](T`& object) const;&]
[s2; &]
[s2; [* Key] should return unique identifier for Value requested with 
ValueMaker derived class. Note that the type of ValueMaker derived 
class becomes a part of the key, so it is not necessary to add 
any info about the ValueMaker into the key. [* Make] then creates 
the corresponding Value and returns the approximate memory consumption 
needed to store that Value. [* MakeValue] first checks whether 
Value corresponding to given ValueMaker and Key are in the cache, 
if yes then it returns Value from the cache, otherwise calls 
ValueMaker`::Make to obtain the Value and stores it to the cache.&]
[s3; &]
[s4;%- &]
[s5;:Upp`:`:IsValueCacheActive`(`):%- [@(0.0.255) bool]_[* IsValueCacheActive]()&]
[s2; Returns true if it is still possible to use Value Cache. This 
special function is intended to solve destruction conflicts at 
the program exit.&]
[s3;%- &]
[s4;%- &]
[s5;:Upp`:`:AdjustValueCache`(`):%- [@(0.0.255) void]_[* AdjustValueCache]()&]
[s2; Adjusts the size of cache based on system memory available. 
The process is driven by parameters that can be set by SetupValueCache. 
Note that CtrlCore (U`+`+ GUI) normally calls this function after 
processing every GUI event.&]
[s3;%- &]
[s4;%- &]
[s5;:Upp`:`:ShrinkValueCache`(`):%- [@(0.0.255) void]_[* ShrinkValueCache]()&]
[s2; Maintains the size of cache based on limit computed in the last 
AdjustValueCache call.&]
[s3;%- &]
[s4;%- &]
[s5;:Upp`:`:SetupValueCache`(int`,int`,double`):%- [@(0.0.255) void]_[* SetupValueCache](
[@(0.0.255) int]_[*@3 limit`_low], [@(0.0.255) int]_[*@3 limit`_high], 
[@(0.0.255) double]_[*@3 ratio])&]
[s2; Setups parameters that govern the cache size. [%-*@3 limit`_low] 
is low limit `- cache will never be reduced if its consumption 
is bellow this limit (default is 4MB). [%-*@3 limit`_high] is upper 
limit `- cache size will never grow beyond this limit (default 
is 2GB). [%-*@3 ratio] defines how much available system physical 
memory can be dedicated to the cache, default is 12.5%.&]
[s3; &]
[s4;%- &]
[s5;:Upp`:`:ValueCacheRemove`(P`):%- [@(0.0.255) template]_<[@(0.0.255) class]_[*@4 P]>_[@(0.0.255) i
nt]_[* ValueCacheRemove]([*@4 P]_[*@3 what])&]
[s2; Removes all Values from the cache that satisfy [%-*@3 what] predicate.&]
[s3; &]
[s4;%- &]
[s5;:Upp`:`:ValueCacheRemoveOne`(P`):%- [@(0.0.255) template]_<[@(0.0.255) class]_[*@4 P]>_
[@(0.0.255) int]_[* ValueCacheRemoveOne]([*@4 P]_[*@3 what])&]
[s2; Removes one Value from the cache that satisfy [%-*@3 what] predicate 
(simply removes the first one that it finds).&]
[s3; &]
[s4;%- &]
[s5;:Upp`:`:ValueCacheAdjustSize`(P`):%- [@(0.0.255) template]_<[@(0.0.255) class]_[*@4 P]>
_[@(0.0.255) void]_[* ValueCacheAdjustSize]([*@4 P]_[*@3 getsize])&]
[s2; Adjusts size information. [%-*@3 getsize] should return the memory 
size needed to store Value passed as parameter or it can return 
negative number to signal that the size has not changed. This 
is very specific function basically only needed to support PaintOnly 
Images.&]
[s0; ]]